Dental tray



Feb. 13, 1923.

2 SHEETS-SHEET l- 6H0: new

. 1,445,499. S. E. DOUGLA'SS.

DENTAL TRAY.

FILED APR. 13. 1922.

Feb.13,1923. j 1,445,499., S. E. DOUGLASS.

DENTAL TRAY. FILED APR. 13. 19:22.

2 SHEETS-SHEET 2.

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Patented Feb. l3, 1923.

SAMUEL E. DOUGLASS, OF RALEIGH, NORTH CAROLINA.

s earns a DENTAL. TRAY.

Application filed April 13, 1922. Serial No. 552,277.

1'0 all 10/10 121- it may concern Be it known that l, SAMUEL E. Don'emss, a citizen of the United States residlng at Raleigh, in the county of lVake and State of North Carolina, have invented certain new and useful Improvements in Dental Trays; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention has for its object the provision of an upper and a lower tray or cup which will retain and. hold in shape the impression of the mouth preliminary to fitting modeling composition and the like, generally used by dentists when taking an impression of the mouth preliminary to fitting artificial teeth, such as plate or bridge work.

The invention furthermore provides a tray which will prevent surplus impression material from lodging; in the throat of the patient or collecting in the mouth, the tray being provided with outlets for theescape of the surplus material when pressure is exerted to conform the material to the mouth.

The invention also has for its object to devise a tray which will admit of practically unobstructed observation of the work so that the tray, when inserted into the mouth, may be properly positioned and thereby obviate several attempts in order to obtain a dependable impression of the mouth for proper fitting of the teeth thereto.

The invention furthermore provides a tray having a handle which acts as a receiver to catch the surplus impression material and which furthermore enables the removal of the tray from the mouth by application of the force to the inner or rear end of the tray, which results in a more ready removal of the tray than application of the force to any other point thereof.

The invention furthermore aims to provide, a tray which will insure a firm anchorage. for the impression material and which will hold back the mucous membrane and prevent interferencethereof with the impression.

Other objects and advantages will be apparent and suggest themselves as the nature of the invention is understood.

While the drawings illustrate an embodiment of the invention it is to be understood that in adapting the same to meet different conditions and requirements, various changes in the form, pro -iortion and minor details of construction may be resorted to without departing from the nature of the invention.

Referring to the accompanying drawings forming a part of the application,

, Figure 1 is a top plan view of an upper dental tray or cup embodying the invention,

Figure 2 is a view of the tray inverted, and as it appears from the lower or bottom side, a

Figure 8 is a side View of the tray,

Figure 4 is a central longitudinal section on the line 4l4; of Figure l,-

Figure 5 is a transverse section on the line 5-i3 otFigure 1,

Figure 6 is a side view of the arch attachment,

Figure 7 is a top plan view of the lower tray or cup,

Figure 8 is an inverted view thereof, as seen from the lower or bottom side.

Figure 9 is a side view,

Figure 10 is a rear view partly in section, as indicated by the line 1010 of Figure T, and

Figure ll is a central longitudinal section on the line 11-11 of li igure 7.

Correspoiuiling and like parts are referred to in the 'iollowing description and desire nated in the several views of the drawings by like reference characters.

The tray or cup comprises a bottom 1 having a centrally disposed raised portion 2 to enter the root of the mouth and an outer upstanding wall 3 slightly incurved towards its upper edge, the rear portion of the wall being of less height than the front and side portions so as not to interfere with the soft palate. A handle 4 springs from the inner or rear end of the tray and extends forwardly thereof with its outer portion curved upwardly, as indicated at 5, to enable the thumb of the hand to grip the same securely. A depression 6 is formed in an edge of the handle 4 to receive the index finger of the hand to the end that the tray may be firmly and conveniently gripped when manipulating the same, The handle 4: is broad and extends beneath the tray and is spaced from the bottom thereof, the space gradually increasing from the inner or rear end of the tray towards the front thereof. A plurality of small openings 7 are formed in the bottom of the tray and constitute outlets for the escape of surplus impression material when pressure is brought to bear on the tray to conform the material carried thereby to the mouth. The surplus material escaping through the outlets 7 lodges upon the handle 4: and may be removed therefrom or removed with the tray after the material has set. The handle 4: preferably forms a part of the tray and the article may be formed from any suitable material according to the finish or nature of the same.

Longitudinal depressions 8 are formed in the side portions of the wall 3 and constitute an anchorage for the impression material, thereby insuring removal of the impression or model with the tray when withdrawing the latter from the mouth after the impressionmaterial has set. The depressions 8 result in outwardly extending ridges which act as restraining means to hold the mucous membrane back and prevent interference thereof when taking the impression.

\Vhile the depressions 8 insure removal of the impression with the tray, nevertheless they do not prevent detachment of the I material from the tray when, it is required to prepare the tray for further service after the previous impression has fulfilled its office.

The lower tray is substantially of U-form and comprises an inner 1 0 and an outer wall 11. The side portions of the walls 10 and 11 flare rearwardly and the rear side portions of the wall 11 have outer extensions 12 which assist materially in holding the mucous membrane back and preventing interference thereof with the work when making an impression. Longitudinal. depressions 13 are formed in the walls 10 and 11 and enable the impression material to obtain a firm anchorage, wherby to insure the removal of the impresion intact with the tray when the latter is withdrawn from the mouth after the material has set. The outer ridges formed. as a result of the depressions 13 serve torestrain and hold back the mucous membrane and prevent interference thereof with the impression. The rear portion of the handle 14 is forked and Y the furcations are partly twisted to provide in effect a flat portion 15 and an edge portion 16, the fiat portion 15 being at the inner or rear end of the tray and lying close against the same and the edge portion 16 being substantially perpendicular to the front portion of the tray. The outer portion of the handle inclines to the tray and springs therefrom intermediate the front and rear thereof, as indicated most clearly in Figure 8. As a result the handle does not interfere with clear observation of the tray when placing the same in position to take an impression of the lower portion of the mouth. The tray and handle are preferably of integral formation and when the parts are stamped from sheet material, the handle may be folded back upon the tray in substantially the same manner as the handle 4 is folded back upon the upper tray.

The arch, crown or roof of the mouth of different patients varies in height and shape and to obviate the necessity of providing trays having the raised portion 2 of different heights and shapes, an arch attachment is provided and adapted to be detachably fitted to the raised portion 2 of the upper tray. It is to be understood that the arch attachment will be provided in different heights and shapes, the attachment best adapted for the particular work being selected and applied to the tray.

The arch attachment comprises a plate 17 and a post 18. The plate 17 is preferably of concave-convex form and the post 18 is disposed near the rear end thereof and is adapted to be inserted in an opening formed in the raised portion 2 of the bot tom of the tray. The plate 17 of the different attachments will vary in size and shape to meet different conditions and the post 18 will be of different lengths to adapt the height of the plate to the height of the roof of the mouth. When the roof of the mouth is flat, it will not be necessary to use the attachment, but when the roof is high and narrow, the attachment may be used to advantage and the one best adapted for the case is selected and fitted to the tray.

lVhat is claimed is 1. A dental tray or cup having outwardly extending ribs on its side walls to provide restraining means for holding the n'lucous membrane back and preventing interference thereof when taking an impression.

2. A dental tray or cup having portions pressed outwardly on its side walls to form inner depressions for anchorage of the im' pression material. and outer projections to act as restraining means for holding mucous membrane back to prevent interference thereof when taking an impression.

3. A dental tray or cup having outlet openings in its bottom for the escape of surplus impression material, and a downwardly inclined handle extending from the inner or rear end of the tray across the bottom thereof and spaced therefrom and act- 10 disposed below said perforation, and an arch attachment comprising a plate and a post, said post projecting through said perforation and resting on said handle.

In testimony whereof I affix my signature in presence of tWo Witnesses.

SAMUEL E. DOUGLASS. Witnesses A. C. CAMPBELL,

W. N. PERRY. 

